This project will be terminated at the end of fiscal year '75 and incorporated under a new Project Title beginning in fiscal year '76. Continued studies on the growth - inhibitory properties of lipophilic acids and related compounds on human cells in culture will emphasize elucidation of the mechanism(s) involved. The scope of these investigations will be expanded to include examination of the effects of teratogenic agents on cells in culture and correlation with the known effects of these teratogens in experimental animals. Further studies on the phenomenon of neurite-like process formation in mammalian cells elicited by short-chain fatty acids will emphasize the following: 1) The roles of calcium and cyclic nucleotides in the regulation of microtubule assembly. 2) The mechanism of induction of the ganglioside biosynthetic enzyme, sialytransferase, by butyrate. 3) The relationship between alterations in membrane glycolipids and glycoproteins and morphological changes.